Charge former



April 6, 1943. T. A. sT. CLAIR CHARGE FORMER Filed Aug. 4, 1941.

Mln 4 /N//// /////,////////UN/ f f//f /f l /1/ f/ f f /H INVENToR T A.st CLAIR liquid fuel through Patented Apr. 6, 1943 UNITED STATES PATEN ToFEIcE 2,315,879 CHARGE FORMER Theodore A. St.

Clair, Pontiac, Mich., assigner to Phillips Petroleum Company, acorporation of Delaware ApplicationAugust 4,1941, serial No. 405,437

(o1. zei-1o) 2 Claims.

This invention relates to a motor fuel system utilizing hydrocarboncompounds having wide boiling-ranges. More particularly it relates to amethod and apparatus for metering a volatile fuel.

An object of the present invention is to provide a method and apparatusfor carbureting h'igh vapor pressure fuels.

Another object of this invention is to provide such a system, operatingwithout the use of pressure reducing regulator means, whereby theeratingwith leed of highly bustion engine.

Another object of the invention is to obtain a reduction of the vaporpressure by cooling the means of a partial vaporization of the fuel.

Still another object is to provide means for keeping the fuel in liquidform andto prevent vaporization thereof, before the fuel enters thevaporization chamber,k

remains in a liquid state. Other objects andadvantages will be apparentfrom the following detailed description taken in conjunction with the raccompanying drawing, forming a part of thisspeciflcation and in which:Figure l is a vertical section, partly in elevation, through a preferredembodiment of this invention, and

Figure 2 is a similar oi' this invention.

Referring now more particularly to Figure 1, the numeral I indicatesgenerally the upper of two main castings makingup the meteringapparatus. This upper casting which may be made of any preferredmaterial, contains a float cham..

view of a modied form ber 23 formed by the circular wall Il and bottomend wall I2. 'I'he upper part of casting I0 forms an adapter and airintake pipe I3 for'an air cleaner, not shown.

Flanged to casting I0 is the lower casting I4 containing a vaporizationchamber I5 formed by an annular wall I 8 and a bottom end wall I1.

This casting also forms the main and lower part I8 of intake pip-e 'I3which is connected in the usual manner to the engine intake manifold.Mounted within this part I8 oi' the intake pipe is a Venturi tube orsection I9 having a main liquid discharge jet 20 formed in conduit 2|which extends through the venturi and communicates -31 in the upper partof casting `other suitable material :tending up into at one end with thevaporization chamber I5. A

at its upper vend with conduit to be slidably mounted upon stem 28 andengage spring 29. External threads on screw 3l engage threads cut intothe interior ofpassase I0. A removable closure member 32 is provided toseal the upper end of passage 3| and allows access to the adjustmentscrew. In this way suiilcient loading may be placed on the oat to secureproper functioning 'of the apparatus during operation of the engine.

Conduit 33 bored within the upper part of casting I0 communicates at itslower end with the interior of float chamber 26 and at its other endwith Ythe interior of the air intake pipe I3. Vapor outlet adjustmentscrew 34 is mounted so as to project into this passage and provides ameans for manually controlling the iiow of vapor through this passage.

Mounted within an aperture formed in wall l2 is a tubular collar 35which extends'down through a similar aperture in wall I1. A fluid tightkengagement between theA collar and the walls prevents leakage from thefloat chamber intothe vaporization chamber. Gaskets of rubberl or may beused if preferred for this purpose as shown at 36. VWelded to the underside of wall I1 is a valve body member 31 having a central passage 38 ofvarying diameters bored therein. The lower end of collar 35 seats withinthis passage as at 38. A valve 39 pre1.'- erably of the tire core typeis mounted within this passage having a depressable head 40 exa centralpassage 4I bored through collar 35 and aligning with passage 33.Projecting from the bottom of oat 21, extends through passage Il incollar 35 ing head 40 of valve 39. In movement of the oat will depresshead 40 opening valve 39 and upward movement of the float will cause thevalve to close. Normally valve 33 is closed and is open only when head40 is held contactbored within wall 23 of casting stem 42 this waydownward Lure l is .vaporization down, permitting fluid to iiow throughthe interior of the valve from inlet passage Il.

A second aperture in wall i2 has a removable plug I3 mounted thereinwhich is centrally bored to form the -main metering orifice: of thepresent device. It lwill be seen by reference to the drawing that fluidcommunication between the float chamber and the vaporization chamberoccurs through this orifice.

An insulating jacket M of cork, or any other similar material suitablefor insulating purposes, it attached to the exterior sides of casting ilso as to surround both the vaporization chamber and the lower part ofthe air intake pipe.

Liquid fuel flows through line 45 which is connected in the customarymanner to the lower end of passage 38. An oil pressure operated shut-offvalve Ii is also connected to line l5 havingran oil pressure line at 41and the customary manual starting lever Il adapted to be operated fromthe driver's compartment.

In operation the shut-off valve shown in Figopened manually or by oilpressure and liquid fuel enters the float chamber through inlet valve 38to a predetermined level as indicated by the reference line A-A. Atfirst, vaporization will take place in the float chamber as well as inthe vaporization chamber. Vapor for-med in float chamber is then carriedinto the air intake pipe il through the vapor balance conduit 3l. Afterthe system has become cool, the temperature of the fuel being reduced tothe at atmospheric pressure so that it will remain in a liquid state,vaporization within the float chamber will cease or be reduced to asmall amount. Vaporlzation will then be practically confined to thevaporization chamber surrounding the float chamber. The partialvaporization of the liquid fuel itself effects a cooling which tends toremove heat from the inner float chamber andthereby reduces the vaporWhen a stream 'of air passes through the Venturi tube Il, the lower endi8 of the air intake pipe Il being connected to the intake manifold ofthe engine, a reduced pressure exists in the discharge jet 2U and in thevaporization chamber Il. As the pressure is lowered, the liquid inchamber li will rise sufficiently above the level A-A to register withthe conduit 2 Fuel flows orifice I3 from the float chamber into thevaporization chamber and out through the main discharge jet into the airstream which carries it into the combustion chamber ofthe engine. jetbeing designed sufliciently large to operate with fuel ineither vapor orliquid form, will un-l der normal conditions discharge the fuel inliquid form. the vapor formed chamber will cause depress sufficiently topermit simultaneous withdrawal of liquid and vapor initially throughconduit 2 I boiling point through extending from said outlet to herewithshown and which will be the equilibrium condition of normal operation.The flow through themain metering jet 43, however, will always beentirely liquid, thus providing accurate proportioning.

Figure 2 shows a modified forrn'of the present i invention in which theair intake pipe ifcontaining a Venturi tube i9' and throttle valve 2l'is a separate, not an integral unit of the vaporization chamber. line orconduit 33' is provided and connects the upper part of the float chamber28 with the air intake pipe. The main discharge iet 20 is connected by asultable conduit 49 to the lower part of the vaporization' chamber i5'.In other respects the device shown in Figure 2 operation to that shownand described for Figure l, except that thefuel in the chamber l5 willvary from the level B--B upon starting after a short running period.

It will beK noted that this device is somewhat similar to a standardgasoline carburetor and therefore may incorporate features such asaccelerating pumps and main load jets, or other refinements as commonlyused on such equipment to improve the operation, if desired. Applicantcontemplates using such refinements with his present device but for thesake of brevity has not included a description or drawing thereof sincethey do not form an essential part of the present invention.

While the applicant has described a specific embodiment. it is to beunderstood that the form,

described, is a preferred ex- 'ample only and that various modificationsmay be made therein without materially departing from the spirit of thisinvention as defined-by the appended claims. v Having thus described myinvention,

l. Charge-forming apparatus for utilizing hydrocarbon fuels, certaincomponents of which ssess a superatrnospheric vapor pressure comprisingin combination, a fuel reservoir having a float controlled inlet, aseparate chamber substantially surrounding the side and bottom walls ofthe fuel reservoir in heat exchange relationship therewith. said chamberhaving an outlet at an intermediate point to form a closed compartmentin the upper portion thereof, a metering orifice in the bottom wall ofthe reservoir, an air passage including a Venturi tube, a fuel dischargeconduit the Venturi tube to subject the chamber to low pressure andcause vaporization of the high pressure components therein, the coolingeect thereby produced being imparted to the fuel reservoir to cool andprevent vaporization of fuel therein.

` 2. The apparatus of claim l wherein a layer of heat insulatingmaterial surrounds the chamber and air passage.

THEODORE A. ST. CLAIR.

to a level C-C

